EKC during a stress test; noise filtering

[fedaykin]

Muscle noise is a big problem with our EKG machines at work. Even the slightest movement will overwhelm the waveform being studied; however, EKGs are done during stress tests which involve quite a bit of vigorous exercise. Muscle noise has a different waveform, but it's basically the same thing being measured.

How is it filtered without disrupting the useful information about the heart?

[dlgoff]

This may be of some interest.
DIGITAL FILTRATION OF ARTIFACTS IN ECG (http://www.urel.feec.vutbr.cz/ra2008/archive/ra2004/abstracts/105.pdf.)